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Articles 284191 - 284220 of 293715
Full-Text Articles in Physical Sciences and Mathematics
Terminal Talk - The Wofford Connection - October 1971, Wofford College Computer Center
Terminal Talk - The Wofford Connection - October 1971, Wofford College Computer Center
Terminal Talk
No abstract provided.
Nuclear-Magnetic-Resonance Studies Of The Semiconductor-To-Metal Transition In Chlorine-Doped Cadmium Sulfide, Frank D. Adams, David C. Look, Carlton L. Brown, Donald R. Locker
Nuclear-Magnetic-Resonance Studies Of The Semiconductor-To-Metal Transition In Chlorine-Doped Cadmium Sulfide, Frank D. Adams, David C. Look, Carlton L. Brown, Donald R. Locker
Physics Faculty Publications
Spin-lattice relaxation times (T1) and Knight shifts were measured for Cd113 nuclei in 12 CdS crystals doped with various amounts of chlorine. Hall coefficients were measured in order to estimate conduction-electron concentrations. Data were obtained for all samples at 300 °K and for some highly doped samples at 77, 4.2, and 2.13 °K. Metallic properties were observed in all samples having electron concentrations n>2×1018 cm-3. At 300 °K, we find 1/T1∝n for nonmetallic samples and 1/T1∝n2/3 when samples are metallic. The latter proportionality continues to hold at lower …
Gravity Investigations Over A Salt Structure Near Lübbecke, Northern Germany, Reinhard K. Frohlich
Gravity Investigations Over A Salt Structure Near Lübbecke, Northern Germany, Reinhard K. Frohlich
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
A detailed gravity survey was conducted parallel to the “Wiehengebirge” northwest of Minden in Northern Germany. The survey localized between Liibbecke and Levern a salt deposit, which is known as “Münder Mergel” salt of the Upper Jurassic. The salt deposit forms a cylindrical structure with an axis striking NWW. With a deep drill hole detailed interpretation was possible using the polygon method of TALWANI, WORZEL and LANDISMAN [1959], The section shapes of salt bodies under eight profiles show asymmetrical figures of two salt units. Both increase in thickness strongly to the northeast, where the salt is interrupted by a fault …
A Preliminary Ecological Study Of Areas To Be Impounded In The Salt River Basin Of Kentucky, Louis A. Krumholz, Stuart E. Neff, Edmond J. Bacon, Jerry S. Parsons, John D. Woodling
A Preliminary Ecological Study Of Areas To Be Impounded In The Salt River Basin Of Kentucky, Louis A. Krumholz, Stuart E. Neff, Edmond J. Bacon, Jerry S. Parsons, John D. Woodling
KWRRI Research Reports
This report includes work that is an extension of Project No. B-005-KY as reported in Research Report No. 43 of the University of Kentucky Water Resources Institute. That project was initiated in April 1968 as Project No. A-019-KY with principal emphasis on physical, chemical, and biological characteristics of the main stem of the Salt River upstream from the proposed damsite for Taylorsville Lake, an impoundment of about 3, 600 acres at seasonal pool. The report includes descriptions of an additional 13 stations along the stream, bringing to 38 the number of permanent collecting sites.
Values for dissolved oxygen ranged from …
Detection And Identification Of Molecular Water Pollutants By Laser Raman Spectroscopy, Eugene B. Bradley, Charles A. Frenzel, John Reeves, Robert Mcconnell, Kay Lane
Detection And Identification Of Molecular Water Pollutants By Laser Raman Spectroscopy, Eugene B. Bradley, Charles A. Frenzel, John Reeves, Robert Mcconnell, Kay Lane
KWRRI Research Reports
Laser Raman spectroscopy is evolving into a primary tool for the Identification of molecular water pollutants. This study pushes the limits of detectivity of carbon disulfide and benzene to ~ 20 ppm in water solutions using a high-resolution Raman spectrometer, cooled detectors, and photon counting techniques. The primary limiting factors were found to be the low throughput and the scattered light performance of the monochromator as well as insufficient laser energy.
An optomized design for a pollution-measuring instrument is suggested, and a prototype has been built which is useful with any value of excitation energy short of sample degrading. The …
Measurement Of Currents In Lake Mead With The Deep Water Isotopic Current Analyzer (Dwica), J. J. Sartoris, D. A. Hoffman, Bureau Of Reclamation
Measurement Of Currents In Lake Mead With The Deep Water Isotopic Current Analyzer (Dwica), J. J. Sartoris, D. A. Hoffman, Bureau Of Reclamation
Publications (WR)
In Nov 1967, a Deep Water Isotopic Current Analyzer (DWICA) was used to study current patterns in the Boulder Basin of Lake Mead to determine if low-quality water from Las Vegas Bay might enter the Southern Nevada Water Project intake on Saddle Island. Secondary objectives were to study the general current patterns in Boulder Basin and the effect of power discharges at Hoover Dam on these currents. Results of current measurements at 3 stations in Boulder Basin are given. Observations indicate a definite possibility that low-quality water from Las Vegas Bay might enter the water intake on Saddle Island. Current …
Investigation Of The Water Table In A Tidal Beach : Final Report, W. Harrison, John D. Boon, L. E. Fausak, C. S. Fang, S. N. Wang
Investigation Of The Water Table In A Tidal Beach : Final Report, W. Harrison, John D. Boon, L. E. Fausak, C. S. Fang, S. N. Wang
Reports
- I. Instrumentation for Measurement of Water Table Fluctuations by John D. Boon, III, and W. Harrison
- II. The Beach Water Table as a Response Variable of the System by L. E. Fausak
- III. Changes in Foreshore Sand Volume: Role of Fluctuations in Water Table and Ocean Still Water Level by W. Harrison
- IV. One-dimensional Finite Element Analysis of the Groundwater Flow by W. Harrison, C. S. Fang, and S. N. Wang
- V. Two-dimensional Finite Element Analysis of the Groundwater Flow by C. S. Fang, S. N. Wang, and W. Harrison
Comment On Electron Scattering In The Image Potential Well, Pavel Smejtek, M. Silver
Comment On Electron Scattering In The Image Potential Well, Pavel Smejtek, M. Silver
Physics Faculty Publications and Presentations
Comments are made on the model of electron injection into SiO₂ proposed by Berglund and Powell. Their assumptions on electron scattering, disregarding the change of the escape cone with the distance from the emitter, lead to serious underestimation of the injected current. Two alternative models of electron injection, based solely on elastic scattering are discussed and do not predict the experimental results. We suggest that observed field dependence of the injected current into SiO₂ indicates that energy relaxation associated with the injected electrons is responsible for the voltage dependence of the current.
An Evaluation Of A Stable Isotope Of Dysprosium For Labeling And Tracing Sedimentary Particles, Charles Glenn Boone
An Evaluation Of A Stable Isotope Of Dysprosium For Labeling And Tracing Sedimentary Particles, Charles Glenn Boone
OES Theses and Dissertations
An evaluation of the application of dysprosium oxide as a tracer coating to surface label sedimentary particles is made. Physical and chemical properties of the labeled sand are studied. Effective diameters and settling properties of the tracer sand are compared with unlabeled sand. A total of 8.51 kg of labeled sand was placed on the beach at Camp Pendleton. Dispersal patterns obtained 1 and 4 hours after tracer injection indicate a general down current mean tracer migration rate of 0.21 cm/sec (0.42ft/sec). An absolute detection limit of 4 or 5 parts per 100,000 and a real detection limit, after field …
Ua77/1 Western Alumnus, Vol. 40, No. 2, Wku Alumni Relations
Ua77/1 Western Alumnus, Vol. 40, No. 2, Wku Alumni Relations
WKU Administration Documents
Quarterly magazine created for WKU alumni. Regular features are Hilltopics, Sports, Alumni Newsgrams and Notes and In Memoriam. This issue includes:
- Graduate School (College) is On Its Way
- Evening Class is Thataway
- The Hilltopper Hundred to the Rescue
- ETV - Keep Watching, It's All in Color
- Student Interns Learn How Government Works
- Significant Statements: The New Year Begins
- Good News for Fishermen: Reservoir Research
- There it Was! Your Homecoming - 1971
- Performing Arts Illuminate the Campus Scene
- Discovery 1 - Uncovering the Kentucky of Antiquity
- Discovery 2 - Reviving the Heritage of Kentucky
- Discovery 3 - The Intercultural Studies Program …
Water Resources News, Volume 3, No. 7, September 1971
Water Resources News, Volume 3, No. 7, September 1971
Water Current Newsletter
Irrigation and Drainage Specialty Conference
First Annual Meeting of the Nebraska Section of the American Water Resources Association
Amendments to Water Resources Research Act
Testified That Corps Would Benefit from New Department of Natural Resources
Industries Must File Permit Applications or Face Legal Action
Price of Air and Water Pollution Clean-Up at $105 Billion
UCOWR Annual Meeting
Senate Subcommittee Approves Water Pollution Control Legislation
Rhode Island Researchers Propose Beneficial Use of Waste Heat
Lake Tahoe Study
The Pseudo-Problem Of Induction, Joseph Hilbe
The Pseudo-Problem Of Induction, Joseph Hilbe
Joseph M Hilbe
Paper I delivered at the IVth International Congress for Logic, Methodology, and Philosophy of Science held in Bucharest, Romania in 1971.
Terminal Talk - The Wofford Connection - September 1971, Wofford College Computer Center
Terminal Talk - The Wofford Connection - September 1971, Wofford College Computer Center
Terminal Talk
No abstract provided.
A Preliminary Ecological Study Of Areas To Be Impounded In The Salt River Basin Of Kentucky, Louis A. Krumholz
A Preliminary Ecological Study Of Areas To Be Impounded In The Salt River Basin Of Kentucky, Louis A. Krumholz
KWRRI Research Reports
This report covers work that is an extension of Project No. A-019-KY. A series of 25 sampling stations was established in the mainstream and tributaries of the Salt River that extend from the source of the stream in Boyle County to a few miles below the site of Taylorsville Darn in Spencer County. Sampling for water chemistry and biota was carried out semimonthly. Data on temperature, oxygen, depth, and discharge, along with analyses for cations (Ca, Mg, Fe, Mn) and anions (PO4, NO3, NO2, CO3, HCO3) have been accumulated and …
Sevier River Basin Floods 1852-1967, United States Department Of Agriculture, Economic Research Service, Forest Service, Soil Conservation Service
Sevier River Basin Floods 1852-1967, United States Department Of Agriculture, Economic Research Service, Forest Service, Soil Conservation Service
Elusive Documents
This chronology of Sevier River Basin floods extends from 1852 to
1967. Most common and destructive are dry mantle floods, which flow as
a muddy mortar-like substance containing 40 to 55 percent water. Hundreds
of tons of protective topsoil are removed from watershed lands,
debris and boulders are picked up as the flow travels down steep stream
channel gradients, and then the flood is debouched into communities and
on to productive cropland.
The Ias Bulletin, V5n5, September 1971, Iowa Academy Of Science
The Ias Bulletin, V5n5, September 1971, Iowa Academy Of Science
IAS Bulletin
In this issue:
--- Officers, Directors, and Section Chairmen, 1971-72
--- Proceedings Progress
--- Business Manager for Proceedings Appointed
--- Submit Manuscripts for Proceedings at Any Time
--- Iowa Science Teachers Journal Will Have Limited Distribution
--- Staff Changes at Drake Involve Academy "Activists"
--- Status of the Iowa State Preserves Advisory Board Uncertain
--- Darling Foundation Issues Catalog of Conversation Education Facilities
--- Are you a Member of AAAS?
--- AAAS Research Grants Awarded
--- AAAS Governance Changes Being Proposed
--- Guide to Upper Iowa River Published By George Knudson of Luther College
--- AAPT-Iowa Section
--- Student Programs …
Analysis Of Water Reuse Alternatives In An Integrated Urban And Agricultural Area, A. Bruce Bishop, David W. Hendricks
Analysis Of Water Reuse Alternatives In An Integrated Urban And Agricultural Area, A. Bruce Bishop, David W. Hendricks
Reports
Intoduction
The growing demands on our existing water supplies and the current problems of water shortage emphasize the need for a comprehensive approach to analysis and planning of water reuse. The primary focus, heretofore, has been on the treatment technology for achieving water reuse.
The concept of reuse, however, should be broadened to consider a totally integrated urban and agricultural system. This necessitates a systems analysis where water reuse, together with all other water dispositions, is considered in the context of its contribution to the total water resources pool of a region.
The components of the water resource system are …
Studies Of The Potential Curve Crossing Problem I. Analysis Of Stueckelberg's Method, W. R. Thorson, John B. Delos, Seth A. Boorstein
Studies Of The Potential Curve Crossing Problem I. Analysis Of Stueckelberg's Method, W. R. Thorson, John B. Delos, Seth A. Boorstein
Arts & Sciences Articles
A detailed critical analysis is made of Stueckelberg's treatment of inelastic transitions at a crossing of two potential curves. Using an asymptotic method analogous to the WKB approximation, Stueckelberg obtained the well-known Landau-Zener-Stueckelberg (LZS) formula for the inelastic transition probability. His method involved the determination of "connection formulas" linking amplitudes associated with his asymptotic approximants on either side of the crossing-point region. Here we show that (a) Stueckelberg's asymptotic approximants are just the WKB approximants for elastic scattering on the adiabatic (noncrossing) potential curves; (b) Stueckelberg's method for obtaining the connection formulas can be put on a rigorous footing, including …
Evidence For The Existence Of Two Stable Sites For Cobalt Impurity Atoms In Aluminum, Arun Venkatachar
Evidence For The Existence Of Two Stable Sites For Cobalt Impurity Atoms In Aluminum, Arun Venkatachar
Dissertations and Theses
Using Fe57Mössbauer spectroscopy, two alternative sites occupied by cobalt (10-4 at. % ) impurity atoms in aluminum have been isolated. The substitutional site A is the stable position after annealing the sample above 840 K, followed by a rapid quench. The impurity atoms in site A are characterized by a single line Mössbauer spectrum (indicative of a cubic environment), a room-temperature f = 0.502 (r. m. s. displ. 0.071 A) and an I. S. (reI. to Fe) = -0.421 mm/sec. For anneals below 770 K the cobalt atoms migrate to site B, which is characterized by a …
Application Of The Method Of Lattice Statics To Vacancies In Aluminum, Larry Boyer, John R. Hardy
Application Of The Method Of Lattice Statics To Vacancies In Aluminum, Larry Boyer, John R. Hardy
John R. Hardy Papers
In this paper the method of lattice statics is applied to the calculation of the atomic displacements about a vacancy in aluminum using a fifth-neighbor force-constant model for the dynamical matrix and the vacancy-host lattice interaction. The strain-field interaction energy between two vacancies is similarly calculated. The main object of this work is to demonstrate the important modifications of earlier results, obtained for a first- and second-neighbor force-constant model, when one uses the fifth-neighbor model designed to give a significantly better fit to the measured phonon dispersion curves. In particular it is demonstrated that the displacements about the vacancy continue …
13th Annual Rocky Mountain Spectroscopy Conference
13th Annual Rocky Mountain Spectroscopy Conference
Rocky Mountain Conference on Magnetic Resonance
Program and abstracts from the 13th annual meeting of the Rocky Mountain Spectroscopy Conference, hosted by the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, August 9-10, 1971.
A Study Of The Limnetic Zooplankton Of Five Flood Control Reservoirs, Glen R. Helzer
A Study Of The Limnetic Zooplankton Of Five Flood Control Reservoirs, Glen R. Helzer
School of Natural Resources: Dissertations, Theses, and Student Research
No abstract provided.
Terminal Talk - The Wofford Connection - August 1971, Wofford College Computer Center
Terminal Talk - The Wofford Connection - August 1971, Wofford College Computer Center
Terminal Talk
No abstract provided.
A Study Of A Divalent Cation-Selective Electrode, William Stanhope Ryan Jr.
A Study Of A Divalent Cation-Selective Electrode, William Stanhope Ryan Jr.
Master's Theses
The ion-selective membrane electrode, recently introduced commercially, has shown excellent promise as a tool for determining ionic activities and concentrations in solution. It was the intent of the author to study the Orion divalent cation-selective electrode with two objectives.
The first objective of this research was to characterize the response of the divalent cation-selective electrode to calcium and magnesium ions in aqueous solutions. The effect of anions, monovalent cations; and pH upon this response was investigated. An examination was made of the response of this electrode to other divalent cations and of the effect of organic solvents on the membrane …
An Investigation Of Some Free Radicals.|Ni.|Pdecomposition Of Nitrosyl Disulfonate Ion In Polar Non-Aqueous Solvents.|Nii.|Preaction Between 2,2-Diphenyl -1- Picryl Hydrazyl And Nitrosyl Disulfonate Ion Free Radicals, Janan Mary Hayes
Theses and Dissertations
Part I reports the stud y of the decomposition of nitrosyl disulfonate ion in DMSO, acetonitrile, and dichloromethane. A multi-step mechanism involving sulfite ion, sulfite ion radical, and nitrosyl monosulfonate radical as intermediates is proposed. The products of the decomposition are nitrosonium ion, hydroxylamine disulfonate ion, and hydroxylamine trisulfonate ion. A competitive chain reaction was observed when the decomposition occurred in DMSO. The chain reaction was insignificant in carefully dried acetonitrile and dichloromethane. Part II reports the study of the reaction between 2,2-diphenyl-1-picryl hydrazyl (DPPH) and nitrosyl disulfonate ion. Product analysis and kinetic data obtained from stopped-flow procedures suggest that …
An Extension Of The Cochran Q Test, Soo-Young Cho
An Extension Of The Cochran Q Test, Soo-Young Cho
Loma Linda University Electronic Theses, Dissertations & Projects
The familiar x 2 test is ordinarily used to compare percentage distributions of categorical data for two or more independent samples. A more accurate com parison of the percentages is sometimes obtained if the samples consist of matched individuals. The NcNemar test is generally used when comparing only two related samples. Where there are three or more samples the Cochran Q test is used. Both of these tests apply only to the case of dichotomized responses. This thesis extends the Cochran Q test to the case where the responses are multinomial. A generalized statistic corresponding to Cochran's result is obtained. …
Elastic Scattering Of Alpha Particles From 12C, Hsi-Chiu Liu
Elastic Scattering Of Alpha Particles From 12C, Hsi-Chiu Liu
Masters Theses
No abstract provided.
Lower Bounds In The Stekloff Problem, Shrikant Narayan Rao
Lower Bounds In The Stekloff Problem, Shrikant Narayan Rao
Masters Theses
No abstract provided.
Stereochemistry And Circular Dichroism Of Trans-Diacidobisdiamine Complexes Of Cobalt(Iii), Jack A. Tiethof
Stereochemistry And Circular Dichroism Of Trans-Diacidobisdiamine Complexes Of Cobalt(Iii), Jack A. Tiethof
Dissertations
No abstract provided.
On The Molecular Theory Of Dielectric Polarization In Rigid‐Dipole Fluids, John D. Ramshaw
On The Molecular Theory Of Dielectric Polarization In Rigid‐Dipole Fluids, John D. Ramshaw
Physics Faculty Publications and Presentations
A molecular theory is developed for the polarization P(r) produced by a weak position‐dependent external electric field E0(r) in a finite fluid system, of arbitrary shape, composed of rigid polar molecules. The theory differs from earlier work in that no assumption is made concerning the form of the electrostatic constitutive relation. [The usual assumption in this regard is that P(r) = (ε–1) E(r) / 4π, where E(r) is the total Maxwell electric field. The “dielectric constant” ε is well defined only if the relation between P(r) and E(r) …